1. Field of the Invention
The present invention relates generally to an interconnection between a pulling motor vehicle and a trailer, and, more particularly, to the interconnection between the pulling motor vehicle and a trailer wherein a trailer-mounted ball connector is provided on the trailer and a hitch ball unit is provided on the pulling motor vehicle.
2. Description of the Prior Art
Trailers are well known in the art. More specifically, trailers that carry other vehicles and that are pulled by a motor vehicle are well known. Even more specifically, trailers that carry other vehicles are often tilted to allow the carried vehicles to be loaded onto and unloaded from the trailer. Vehicles carried by such trailers include land vehicles and watercraft such as boats. A trailer carrying watercraft is often referred to as a boat trailer.
For trailers that carry other vehicles and that are tilted to allow the carried vehicles to be loaded onto and unloaded from the trailer, it is desirable to maintain the interconnection between the trailer and the pulling vehicle even as the trailer is tilted up or down. In this respect, throughout the years, a number of innovations have been developed relating to trailers that carry other vehicles, wherein the interconnection between the trailer and the pulling vehicle is maintained even as the trailer is tilted up or down, and the following U.S. patents are representative of some of those innovations: U.S. Pat. Nos. 2,817,537, 3,944,259, 4,564,209, 6,003,892, and 6,575,488.
More specifically, U.S. Pat. No. 2,817,537 discloses a boat trailer in which specially designed articulated portions of the trailer itself are rotated or translated with respect to each other in the trailer as the trailer is either tilted up or down. It is noted, however, that there are many trailers currently in use that do not have such specially designed articulated portions. In this respect, it would be desirable if a device were provided that allowed the interconnection between a trailer and a pulling vehicle to be maintained even as the trailer is tilted up or down without requiring the trailer to have specially designed articulated portions allowing maintenance of such trailer-to-vehicle interconnection.
U.S. Pat. No. 3,944,259 a trailer jacking device in which the trailer has a specially designed trailer tongue frame, an adjustable pivotal strut, and a lockable wheel connected to the strut. It is noted, however, that there are many trailers currently in use that do not have such specially designed frames, struts, and lockable wheels. In this respect, it would be desirable if a device were provided that allowed the interconnection between a trailer and a pulling vehicle to be maintained even as the trailer is tilted up or down without requiring the trailer to have specially designed frames, struts, and lockable wheels allowing maintenance of such trailer-to-vehicle interconnection.
U.S. Pat. No. 4,564,209 discloses a trailer hitch assembly that has a complex arrangement of upper and lower horizontal rails and a carriage that provide for transverse movement of the carriage. Such transverse movement is not needed with a boat or other vehicle trailer. Therefore, it would be desirable to provide for the maintenance of an interconnection between a trailer and the pulling vehicle even as the trailer is tilted up or down while avoiding a complex arrangement of upper and lower horizontal rails and a carriage that provide for transverse movement of the carriage.
U.S. Pat. No. 6,003,892 discloses a boat trailer tongue lowering jack apparatus that requires one screw jack element connected to the pulling and another screw jack element connected to the trailer. Trailers that are currently in use do not have such a screw jack element. Therefore, it would be desirable if a connection between a trailer and a pulling vehicle do not require a specially designed screw jack element to be connected to a trailer.
U.S. Pat. No. 6,575,488 discloses a vertically adjustable trailer hitch which is bolted and secured to fixed vertical adjusted positions. There is no continuous movement of the adjustable trailer hitch between the trailer and the pulling vehicle. Therefore, this trailer hitch does not permit a conventional boat trailer to be tilted up or down while maintaining an interconnection between the trailer and the pulling vehicle.
Thus, while the foregoing body of prior art indicates it to be well known to use an interconnection between a trailer and a pulling vehicle that allows the trailer to be tilted up and down without breaking the interconnection, the prior art described above does not teach or suggest a trailer ball raising and lowering apparatus which has the following combination of desirable features: (1) provides that the interconnection between a trailer and a pulling vehicle is maintained as the trailer is tilted up or down without requiring the trailer to have specially designed articulated portions allowing maintenance of such trailer-to-vehicle interconnection; (2) provides that the interconnection between a trailer and a pulling vehicle is maintained as the trailer is tilted up or down without requiring the trailer to have specially designed frames, struts, and lockable wheels allowing maintenance of such trailer-to-vehicle interconnection; (3) provides for the maintenance of an interconnection between a trailer and the pulling vehicle as the trailer is tilted up or down while avoiding a complex arrangement of upper and lower horizontal rails and a carriage that provide for transverse movement of the carriage; and (4) provides a connection between a trailer and a pulling vehicle does not require a specially designed screw jack element to be connected to a trailer. The foregoing desired characteristics are provided by the unique trailer ball raising and lowering apparatus of the present invention as will be made apparent from the following description thereof. Other advantages of the present invention over the prior art also will be rendered evident.